Metalworking machine



-March 26, 1945. H, BROWN 2,397,122y

METALWRKING MACHIENE Filed .July 1e, `1941 v 3 snetsfsneet 1y' `March26? 1946. H. W BRQVVN METALWORKING MACHINE Filed July 16, 1941 3Sheets-Sheet 2 *fMal'Ch 26, 1946. H. w. BROWN l i 2,397,122.

MTALWOR'KING MACHINE Y I' A Filed lJuly 16', 1941 5 Sheets-Sheet 3Patented Mar. 26, 1946 :isst/,122E

Harry W. Browm Cleveland, zhiofass'ignor to The National Acme Company,Cleveland, a corporation of Ohio Ohio,

Application Juiyis, imnjserialNo.f4oa59s (ci. 9o-iam' 2 5 Claims.

This invention relatesto metal workingmachines such for instance, asmilling machines and particularly to what are known as Vcam millingmachines, the object of the invention being to provide a hydraulicallyoperated cam. milling machine in which the master cam is not onlyhydraulically operated but, in turn, controls through the medium ofvalve mechanism, hydraulic means for shifting the milling cutter withthe result that kvery accurate Work is produced in accordance with thecontour of the master? cam and which accuracy it has heretofore beenfound difficult if not impossible to obtain in milling machines,especially those electrically operated and those hydraulically operatedon asingle circuit or servo principle.

` veryv accurate and more sensitive to movement.

Furthermore; an inexpensive mastery cam oi light weight can' be usedsince it docs not directly shift a heavy moving part such asv the toolslide. In the present' improvement, the valve housing ,being rigidlysecured tothe cutter slide for movement therewithand its val-ve; stem orpiston mov- 1 able 'relative to this housing'and alone Operated bythe-master cam, a dual movement offthe parts A further object of theinvention is the proy vision of an improved milling machine in which themilling cutter slide, instead of being directly operated by the mastercam, is operated hydraulically through the medium of valve mechanismcooperating with the cam, a part of which valve mechanism is carried bythe cutter slide for movement therewith and another part is Voperated bythe master cam resultingy in increased accuracy since the master cam isentirely relieved oi" any pressure exerted by the cutter head and is,therefore, much more Vsensitive to movements and itis, consequently,much more accurate than heretofore possible. This is made possiblebecause of the hydraulic balance ofthe spool design of the pilot tracervalve.

It is very important in order to mill an accurate cam, which has to beheld or cut within .001 in lead since this lead on the cam controls thecutting action of the milling tool, that the means controlling the upand down movement of the tool carrier or cutter slide be operated withsuch accuracy that the milling tool will reproduce and mill cams exactlyin accordance with the master cam.

Prior to the present improvement, this operation was accomplishedusually Hby electrical means, solenoid electric contacts operating thelead screw that shifted the cutter slide, but this mechanism is neitheras accurate' nor as'eicient as hydraulic means with independent pilotcontrolv and where also, as heretofore, the'tool slide was operated upand down directly from the master cam, accuracy of the work was notpossible for it will be noted that, inthe present improvement, themaster cam is entirely relieved of any pressure exerted by the slidingcutter head and only controls the action of the pilot tracer valve spoolor piston -so that the mechanism is 1 `is, therefore, obtainedWithincreased accuracy. "ln-the drawings laccompanying and forming apart of` this `specication,- Fig, 1 f working machine shown in the formof a milling is a side `view of this-improved metal machine.

' Fig; y2` is a partly sectional view "of the master4cam-'controlled"pilot tracer; valve taken on line 2f-2 ofliig.` 3;

` Fig; 3A-is a top viewf thereof.

Fig. -4 is-a crossfsecti'onal view taken on line Fig 5^isaverticalfsectional view taken v"on line 5-5 of Fig. 3,-and

Fig .-6 isa vertical sectional view taken on line positions of thepiston valve' relative to its ports. Similar referencecharactersindicate correspending partsfin the-several views.

-Beioreexplaining indetail the present improvement andfitsfmode ofoperation, it is to be understood that the invention is not limitedv tothe details of construction and arrangement of ments and thatthefphraseology employed is for the purpose of" description and not oflimitation.

This metal Working'machine when inthe form of acam millingmachinecomprises a suitable -framework or base 2 having at one end, asthe lefthand endshown in Fig. 1, an upright column Ii slidingly'supporting a lshiftable tool support or head carryinga rotatable millingcutter-spindle frotatedb'y a variablespeed motor -6v a1- Vthough, ofcourse,` this 'cutter spindle may be .driven either by gears 0r a belt.

Centrally of the base 2 is arctatable work support or table 1 carried bya slide 8 and having awork holder 9 anda Work holding support lf3. Theltable 'l and lits slide Bmay 'be' shifted forward orbackward dependingupon the depth of the grooveV cut by the milling cutter, by means v fofa lhand wheel H, and they usual Vconnecting means. This table ,l yisrotated by hydraulically .operated"meansV whichnfor this purpose,comprises a hydraulic unit comprising v'a motonl downV in accordance`with the contour as .willgbetreadily understood.

By reason ofthe fact ythatfthe valve housing operating through a feedcontrol valve I3 to a control valve |4 and iluid motor driving means I5rotating a worm shaft I6 cooperating with suitable connecting means andby means of which the table 1 is rotated. J

This worm shaft I6 controls not only the rota.- tion of the rotary worksupport or table'l but also controls 2Y rotation of the interchangeablemaster cam' |'1 which is in fixed position on the upright column 3 ofthe base. The worm shaft I6 has a splined connection with the worm 'I8'that rotates the m-aster cam I1 so that this lshaft I6 may slide backand forth with the table and according to the position of the vmillingcutter relative to the work. v

This master cam I1 controls the shifting or sliding movement verticallyof :the milling `cutter on the upright column 3 through the medium ofanother hydraulic unit somewhat similar to that hereinbefore describedand comprising a moi$ l, a Vfeed control valve20, a valve 2| andrafluidj'motor .22 which rotates .a worm shaft 23 havinga ybevel gear 24in mesh with asimilar .igear 251secured'to a lead screw 26 cooperatingwith afnutjof the cutter head for shifting the Vcutter; head vertically.lThe, operation .of this fluidmotor is controlled by the master cam I1-throufghfthevalve k2| which is controlled by the pilot Atracervalve21., the casing or Vhousing 21 off which -is adjustably'mounted on the`milling cutter head in any suitable manner for movement VVVtherewithwhile the spring pressed spool or piston ,28 of this valve hasa tracer roller 29 in direct engagement with the master cam I1lso yas L-to, followV the contour of that cam. Consequently, as thepistonorspoolis moved up orfdown. j

the various ports of the valve, as A, .B,C, D and E are opened or closedshifting `the valve 2| :and

,the fluidgmotor 22 isV operated in accordance therewith to rotate theshaft 23 and therebythe worm shaft 26 which, through-the medium of thenut carried by thecutter head, moves-the cutter .head a n i, therefore,the milling cutter `up or ofthe cam 21, is adjustably .mounted ,onvthesliding milling has a ymovement independent of the movement of i t scasing andisoperated and controlled .by V tliemaster cam, it followsthat, whenever the` roll- Y V`er 29 and its valvespool 28 moveinanupward .gondownward direction, lthe cutter head-slide also Emovessimultaneously in an upward or downward direction and this automaticallycloses or'opens the by-pass of thevalve mechanism.

lIt will thus vbe observed that the rotarywork table is hydraulicallyoperated and the-hydraulic V unit for operating this table also operatesthe lmaster VVcam which, in turn, controls the pilot tracer valve thatcontrols the four-way valves I4A and 2| of the hydraulicunits by meansofwhich the vmillinggcutter is shifted vertically soas accurately tofollow whatevercontour the master cam Ymay have.

lf 2,397,122 f cutter head 4 While the valve spoolor Apiston 28 Vandstop: the fluiddrives I5 and 22.

o f-'oil required ltofactuate the fluid drives I5and -22 does not passthrough the pilot. tracer valve.V

ment thereof is-stopped, as illustrated in Fig 6. The tracer roller, 29following aY decline in the master cam allows pressure to pass into theport A causing the cutter head to move downwardly carrying the valvebody per .001V downwardly of the tracer roller, as illustrated in Fig.2, and when the tracer roller stops, the cutter head carries the Y valvebody intov a stopped position,Y as illustrated inFig.6. Y

' Thus, this metal working machine operated by a. pilot tracer vvalve 21(Figs. 2, 3, 4, 5 and 6).

The pilot tracer valve circuit operates the pilot valves I4 and 2| andthese valves, in turn, start The valves YI4 and 2| arepilot-operatedfour-way spring centering valves. Whenthe pilot tracervvalve spool 28 moves into upward position (Fig,

5) pilotpr'essurepasses through the port D (Fig. 6) and its line,.shifting the'valve' 2| and starting rthe fluid drive 22to V,drive thespindle head 4'upwardly by the gearing. 23--24-+25- i2 6.'When the pilottracer valvespool Zamoves downwardly,

pressure passes tothe port A,v shiftingthe'valver .2| in the oppositedirectionand driving; the head Y`4 downwardly. -`Whenthepllottracer-,valve spool .28 is in mid-position. pressure is on portE (Fig.

51, line en (Fig. Y1) Ypassing through the; direction control valve 3(Figui), ,shifting the ,valve I4 and starting 'the fluid ,driven 5,therebyrotating the 'table in the directlonpredetermined by'ahandcontrol valve.

on the head 4 with'micrometeradjustment,to

enable the operator to posti'onthe cutter relativeV tofthe work r9andthe cam or template |1. By

turning the micrometerscrewiinj a directionv to cause the pilot tracervalveto move'A downwardly,

/the cutter'headwill' move upwardly. This micrometer adjustmentiis/graduated tfo' read in .001".

moved up .001 the head willfmove down..0 0l". This pilot tracer valvehasnoldual linkage-fit is )operated ldirectly by the'cam for template I1.

The valve. 21 Yis .connected'by a flexible conduit :30 with thehydraulic ,unit controllinggthe rota- Y tion ofthe work table s o thatas jthe'tra'cer vroller 29'rises or descends Vby Vtherota'tion ofthe'lmaster cam I1, theport E'isopened'to'draininproporvtion to thedecreasing volumeofjthe oil'or-'u'id drive of the work table, thereby'to decrease the rotary feedmovement of thetableiandsd provide a constantfeed of cutter 1`n'angular vor ,parabola milling. In other words, vifthetable moves slowly;

the; proportion of the j oiljthereby controls. the

master camjin accordance withthat slow move- Yfast, f the oil likewisement. If, /onfthe otherfhandathe itablefmov'es that'its speed isincreased and theyv both have to synchronize-fotherwise, there'will beanerror in Athecurve of'thfpm ,9 and mlster cam l1. By having the valveyhousingA .'21r Vadjustablyv se'- cured,l thecutter andcutteriheadj'canbe adjusted lto suitanyheightor dimension of thelwork tobe milled without.l disturbing the mastergcam or the movementofzthe.dual valve .sothat 'it may be said'thejvalvehas a triple movement;V

Obviously, this samefcam' Lcontrolled valve t mechanism couldbegusedinvarious forms oil ---rnetal working machines requiring step ,turningor form turning Q fzidiierent diameters and difjferentjlengthsandemploying a cuttingtoolor grinding. y*lll/kwel .whichihas to .Ice .movedforward i' orY backward YandV controlled by' a master canito The volumeVTherefore, if the E'pilot tracer-,valve is -controls themaster cam soeters.

ahem-2a machine parts of different shapes diam- It is to be understoodthat by describing in detail herein any particular form, structureorarrangement, it is not intended tov limitthe invention beyond theterms of the several claimsor the requirements of the prior art. 'V

Having thus explained the nature of my said invention and described away of constructing and using the same although withoutattempting to setforth all of the forms in which it may be made or all of the modes ofits use, I claim:

1. In a cam milling machine, thecombination of a slidingly supportedrotatable table, ahydraulic unit for rotating said .tablel and includinga worm shaft connected therewith and with the hydraulic unit, a slidingtool support adapted to carry a tool such as a milling tool, a hydraulicunit for shifting said tool support and vincluding a lead screw, andmeans for `controlling the operation of said second hydraulic unit andthereby the shiftable movement of the tool support and comprising arotatable cam havinga fixed position against movement relative to thetool support and a splined connection with the table operating wormshaft whereby it is `rotated thereby, and valve mechanism comprising ahousing connected to the tool support for movement therewith and apiston movable relative to the housing by the cam.

2. In a cam milling machine, ythe' combination of a slidingly supportedrotatable table, 'a hydraulic unit for rotating said table and includinga worm shaft connected therewith and with the hydraulic unit, aslidingtool support adapted to carry a tool such as a milling tool,'ahydraulic unit for shifting said tool supportv andinc'luding a leadscrew, and means for controlling the operation of said second hydraulicunit and thereby the shiftable movement of the tool support andcomprising a rotatable cam having 'a fixed position relative to the toolsupport and a splined connection with the table operating worm shaftwhereby it is rotated thereby, and valve mechanism comprising a housingconnected to the tool support for movement therewith and a "pistonmovable relative to the housing by the cam, said valve mechanism havinga series of ports opened i by the cam operated piston thereby to controlthe tool operating hydraulic unit to shiftl the tool support and housing`in accordance with the contour of thecam, the shifting of the housingeffective to close the ports thereby to stop operation of said hydraulictool operating unit.

3. In a cam milling machinegthe combination of a rotatable work support,hydraulically operated means for rotating said work support, a slidingtool support carrying a tool suchA as a milling cutter, hydraulicallyoperated means for shifting said tool support, means for shifting saidtool support in accordance withl the work tobe done and comprising a camfiXedly supported 'independent of the work support, a valve cooperatingwith the cam for controlling the operation of said last hydraulic means,and means connecting said valve with the work support hydraulicallyoperating means whereby the feed of the table is also controlled by saidvalve.

' valve.V

port and a dual movement valve, and means connecting said valve withlthe means for rotating the work support wherebythe feed movement ofsaidwork -support is also controlled by said support, hydraulic means forshifting the tool support. ymeans for controlling the operation of saidhydraulic operating means of the tool support and comprising a rotatablecam fixedly supported independent o f the work support and a valve, anda conduit connecting said valve `with the hydraulic means for rotatingthe `work support whereby the feed movement of said rwork support isalso 'controlled by said valve. y.

6. In a metal working machine having a base and a fixed uprightsupporting column, thecombination of a work support mounted on the base,a shiftable tool support mountedr on the fixed column, a lead screwforoshlfting the tool support, fluid means for operating said leadscrew, fluid means for rotating said work support, and means forcontrolling the operation of said first fluid operated means andcomprising a cam pivotally supported on the fixed column for rotationand valve mechanism comprising a housing carried by the shiftable toolsupport and a spool piston mounted in said housing and having directengagement with the fixed rotatable cam for controlling the operation ofsaid first fluid means thereby to shift the tool support and rotate thework support.

'7. In a metal working machine, the combination of a rotary worksupport, fluid means for operating said work support, a shiftable toolsupport, a lead screw for shifting said tool support,v fluid meansforoperating said lead screw, means for controlling the operation of saidlast fluid means and comprising a cam carried by a fixed support, apiston valve cooperating with said cam and a valve housing carried bythe tool support and shlftable therewith whereby movement of thepiston'valve will operate the lead screw -operating means to shift thetool support and housing in accordance with the contour of the cam, themovement of said housing effective to stop operation of the lead screw,and means for shifting said rotary work support toward and ffrom thetool support.

8. In a metal working machine, the combination of a rotary work support,fluid means for operating said work support, a shiftable tool supl port,a lead screw for shifting said tool support,

4. In a metal working machine, the'combination of a rotatable worksupport,` a shiftable tool support, means for rotating the work support,means for shifting the tool support, means for controlling the movementof said tool support shifting means and comprising ajrotatablecamflxedly supported independent vof the work supfluid means for operatingsaid lead screw, means for controlling the operation of said last iiuidmeans and comprising a cam carried by a fixed support, a piston valvecooperating with said cam, and a valve housing carried by the toolsupport and shiftable therewith whereby movement of the piston valve`will operate the lead screw operating means to shift the tool supportand housing in accordance with the contour of the cam. the movement ofsaid housing effective to stop operation of the lead screw, and fluidmeans for operating said cam. I

9.l In a metal working machine, the combination of a rotatable worksupport, fluid operated means for rotating said support, a shiftabletool support, a lead screw for shifting said too1 support, fluid meansfor operating the lead screw, and means for controlling the operation ofsaid last fluid means and comprising a rotatable cam,

a ported valve having a piston cooperatingwith ing the tool support, andmeans for controlling the operation of said fluid operated means andcomprising a rotatable cam carried by a fixed support, a piston valveand a ported housing, one carried by the tool support and shiftabletherewith and the other in engagement with the rotatable cam formovement thereby, thereby to shift the tool support in accordance withthe contour of the cam.

21. In a metal working machine, the combination of a rotatable worksupport, iluid operated means for rotating it, a shiftable tool support,means including fluid operated means for shifting the tool support, andmeans for controlling the operation of said fluid operated means andcomprising a rotatable cam carried by a iixed support, a piston valveand a ported housing, one carried by the tool support and shiftabletherewith and the other in engagement with the rotatable cam formovement thereby, thereby to shift the tool support in accordance withthe contour of the cam, and means connecting the'fluid operated meansfor rotating the work support with the cam for rotating said cam.

22. In a metal working machine, the combination of a rotatable worksupport, uid operated means for rotating it, a shiftable tool support,means including fluid operated means for shifting the tool support, andmeans for controlling the operation of said second uid operated meansand comprising a rotatable cam carried by a fixed support, a pistonvalve and a ported housing, one carried by the tool support andshiftable therewith and the other in engagement with the rotatable camfor movement thereby, thereby to shift the tool support in accordanceWith the contour 35 tour of the cam.

of the cam, and means connecting the uld operated means for rotating thework support with the cam for rotating said cam, said cam alsocontrolling the operation of said work support.

23. The structure of claim 8 in which said last fluid operating meansincludes means for also controlling the operation of the Work support-24. In a metal Working machine, the combination of a rotatable Worksupport, a shiftable tool support, means including fluid operated meansfor shifting the tool support, and means for controlling the operationof said fluid operated means and comprising a rotatable cam pivotallysupported by a fixed support and having its pivotal axis at an angle tothe axis of the rotatable work support, a piston Valve and a portedhousing, one carried by the tool support and shiftable therewith and theother in engagement with the rotatable cam for movement thereby, therebyto shift the tool support in accordance with the contour of the cam.

25. In a metalworking machine, the combination of a rotatable Worksupport, a shiftable tool support, means including fluid operated meansfor shifting the tool support, and means for controlling the operationof said fluid operated means and comprising a rotatable cam pivotallysupported by a iixed support and having its pivotal axis at right anglesto the axis of the rotatable work support, a piston valve and a portedhousing, one carried. by the tool support and shiftable therewith andthe other in engagement with the rotatable cam for movement thereby,thereby to shift the tool support in accordance with the con- HARRY W.BROWN.

